joyent/node — pull request #1948 by TooTallNate (2011-10-26 18:12:01+00:00)
Title: Export isDate(), isArray(), isRegExp() and isError() from util.js

As per the discussion at: http://groups.google.com/group/nodejs-dev/browse_thread/thread/b08970166e4670cf

Tests and docs included :)